Ammonia Diaper Rash: Causes, Treatment & Prevention (with Pictures)

By April Duffy •  Updated: 04/30/24 •  16 min read

Ammonia diaper rashes are not a new problem to parents by any means. In fact, baby powder companies were using ammonia to sell their talcum powders back when cloth diapers were the only option in the 1930’s to 1950’s (the first disposable diaper didn’t hit the US mass market until 1948).

Here are a few advertisements from that era talking about the irritation and “scalding” of “ammonia diaper” (i.e. ammonia burns):

But of course today, we know that talcum powder poses a significant cancer risk, and have a lot more products at our disposal. We also have better cleansing products and washing machines that can help prevent ammonia in the first place, so keep reading!

Important note: This article is for information purposes only. It exists to help you with rash prevention and give you a better understanding of diaper rashes so that when you discuss your baby’s rash with your pediatrician you’re more informed.

All rashes that don’t clear up quickly, or that are recurring often, should be checked by a pediatrician to ensure they are manageable and do not require medical attention and/or medication. Never, ever, take another mom’s advice or an online article’s say so over the expert opinion of a medical professional who has spoken to you about your baby’s health.

When in doubt, always check with a pediatrician!

Is Diaper Rash Common with Cloth Diapers?

Of course, all this talk about ammonia rash over the past 100 years is likely to make you ask if diaper rash is more common in cloth diapers, but rest assured it’s not.

I recently interviewed Dr. Lyndsey Garbi, a board-certified Pediatrician and Neonatologist, and the Chief Pediatrician of Blueberry Pediatrics about diaper rash, and she said, “Diaper rashes are less frequent with cloth diapers,”

You can read my complete interview with Dr. Garbi about diaper rash here, but the long story short is that while cloth diapers can cause fewer rashes than disposable diapers, diaper rashes are common. The truth is there are a multitude of causes of diaper rash including food sensitivities, teething, product sensitivities, fabric sensitivities, wash issues, and yes, ammonia/ph imbalances. Ammonia is very irritating to skin, and it’s a common cause of diaper rashes in both cloth diapers and disposable diapers.

Sometimes you can tell what type of rash you are dealing with visually, however, if the treatments you’re using aren’t helping after a day or two, if it looks worse after treatment, if it’s causing discomfort to the child, if it looks fungal, or if you’re becoming uncomfortable handling it alone, don’t delay further and contact your pediatrician.

What Does Ammonia Diaper Rash Look Like? (Ammonia Diaper Rash Pictures)

While I am not a doctor, and don’t play one on t.v (see the disclaimer above), I have been speaking about cloth diapers and rashes with the tens of thousands of moms in the Cloth Diapers for Beginners community for over seven years now, and can confidently say that rashes caused by ammonia burn or a similar irritation (more on the causes in a moment), do actually look different than other types of diaper rash.

Specifically, this type of rash looks intensely, almost neon, red. If it worsens blisters can also appear, which is why this type of rash is often called, “ammonia burn.” This bright redness looks very different than the slight redness caused by typical diaper rash (contact dermatitis), or the bumpy and/or white filmy types of rashes that are caused by yeast.

The angry redness and/or blistering that comes from ammonia rashes can appear across the entire diaper area, or only around the anus area (this is a good indication the cause is food related, but more on that in a moment).

This type of rash also often appears only around the top of the diaper, and where the leg elastics touch the legs, but it’s important not to confuse these markings with sock marks.

Sock Marks vs. Ammonia Diaper Rash Marks

“Sock marks” are called that because they resemble the same indentations and slight redness that your ankle gets after a day of wearing a snug sock. While your skin because slightly red and has some light indentation, which will quickly fade, there’s no pain or discomfort as a result.

Rash lines however don’t fade and don’t usually have indentations, but in fact, can be raised from inflammation of your baby’s skin.

What Causes Ammonia Rashes?

Ammonia rashes, sometimes also called ammonia burns, chemical rashes, chemical burns, or high-ph rashes can have many causes, but in most cases, they are caused by these seven problems:

1) Washing Diapers with Laundry Soaps

I’ve written at length about why it’s not a good idea to wash cloth diapers with DIY or commercial laundry soaps here, but in short, soaps don’t work in modern washing machines.

Modern washing machines are designed to use very little water and energy (agitation), and so they are really only designed to work with modern laundry detergents.

Unlike detergents, which contain low-sudsing surfactants that are designed to grab onto dirt and rinse it away with little water, soaps create a soap scum that if not rinsed completely away (requiring a lot of water and scrubbing)

2) Washing Diapers with Charlie’s Soap

I know, I just said no soaps so it probably seems redundant I’m saying not to use Charlie’s Soap but that’s because I know some of you are sleuthy enough to read the ingredients and realize has surfactants, so technically, it’s a detergent.

Problem is, it’s still going to cause burns. I don’t recommend Charlie’s Soap (especially the powder version) for cloth diapers because through my research and personal observation of others’ results I believe it has a unique blend of ingredients specially formulated to give babies rashes. You can read all about the mixture of ingredients that cause the problem in my full post about Charlie’s Soap here, but in short, if you’re using it and your baby has ammonia burns, it’s pretty darn likely it’s the cause.

3) Using High-PH Additives in Your Laundry

Usually bleach.

If you’re using bleach in your diaper laundry long-term, especially if you’re using it to hide ammonia smells, (there are many natural causes of ammonia in your cloth diapers, which I will touch on in a moment) the PH of your diapers could be so high that it’s irritating your baby’s skin as soon as they wet their diaper (with urine, which of course is a high PH substance to begin with).

Here’s a quick visual to show you the PH of many laundry substances, so you can see how long-term use of bleach and detergent can exacerbate an ammonia problem in your diapers.

PH Scale

Bleach and ammonia don’t mix, not only because they create a toxic gas (chloramine gas) that irritates the eyes, nose throat and lungs, but with diapers mixing the two can also create a PH level that can be irritating to a baby’s wet skin.

4) Using Too Much Detergent in Your Cloth Diaper Laundry

This one is the most common cause of ammonia smell in cloth diapers, and can definitely be the cause of ammonia rash if left unsolved.

Once again, I have a lot of information about detergent buildup on cloth diapers in this article, but the gist is that if you’re using an amount of detergent that is too much for your load of laundry, using detergent in your rinse cycle, or if you’re overstuffing your washing machine past its maximum load capacity (meaning it won’t have enough water to get rid of the detergent you put in), you likely have layers of excess detergent, soil, and bacteria building up on your diapers.

This layering of excess detergent, and the soil and ammonia that is stuck to its surfactants, will soon start to smell and the PH will also help turn urine into ammonia quickly. Soon, as soon as your baby wets the diaper it will stink of ammonia and after some time will also cause ammonia burns.

5) Not Using Enough Detergent in your Cloth Diaper Laundry

I know, I know, I just went on about using too much detergent, and now I’m going to add too little detergent to the list; it’s enough to make you crazy!

But using too little detergent in your wash cycle, especially if you have hard water, can also cause layers of ammonia, bacteria, and soil to buildup on the surface of your diapers.

The difference here is that often the first smell you notice will be a barnyard or just “dirty” smell, but over time, if not corrected, an ammonia smell hit as soon as baby wets and ammonia rashes are soon to follow.

6) Medical/Bodily Ammonia

The thing that makes ammonia in cloth diapers a bit frustrating, is that sometimes it’s not due to any outside source; sometimes, the ammonia is a result of something going on inside the body. 

Some of these are cause for concern, and others are not. Here are just a few: 

(Sources: Healthline and Medical News Today)

In these cases, the ammonia concentration is usually low and an ammonia smell in your diapers is your first sign, rather than a rash. However, these conditions can cause a rash soon after the smell is detected as a result of it building up over time, not being washed away well, or working in combination with some of the other causes that I outlined above. 

While I cannot offer you medical advice, since I lack any health-related qualifications or expertise, if you’re smelling ammonia in your baby’s diapers and can’t identify a wash-related cause, I suggest seeing your pediatrician to talk over the problem and ensure nothing that needs attention is being overlooked.

To prepare for your pediatrician’s visit, increasing your baby’s fluid intake may help. 

7) Food Sensitivities

This one is the hardest to nail down, I know because it caused me and my daughter a lot of high-PH rashes before I could figure out her sensitivity — yogurt.

The top sign that your chemical rash or chemical burn-like rash is being caused by a food sensitivity throwing off your baby’s poop PH is that the rash will usually start right around the anus, and will flair up only when they soil their diaper.

These rashes are also FAST. I can recall trying to change my daughter’s poopy diapers so quickly that I often did so in mid-poop, and she would STILL get a rash. It was intense.

If this sounds all too familiar, start by treating the rash with topical products (more info below) and keep a food diary. If you can’t identify an offending food because your baby tends to eat the same foods daily, start by eliminating one of their regular foods for a week and see if that helps, if not switch to another food elimination the following week, and so on until the rashes calm down and you can identify the offending food.

How Do You Treat Ammonia Diaper Rash and Ammonia Burns on Baby’s Skin?

Aside from correcting the cause, which I’ll speak about more in a moment, you can start to heal your baby’s ammonia diaper rash with a good diaper cream under a layer of cornstarch.

No, cornstarch won’t cause a yeast rash (more on the truth about cornstarch for diaper rash here), but much like our great-grandmothers found out from those 1930’s and 1950’s talc powder advertisements a dry, hydrophobic powder actually works wonders for ammonia rash.

Cornstarch is a great way to get all the benefits of talc without cancer risk!

For this type of rash, especially the tough blistery ones, I personally recommend a good strong zinc cream like Desitin maximum strength or Penaten under cornstarch.

Desitin Maximum Strength Baby Diaper Rash Cream
$9.93 ($2.48 / Ounce)

Desitin Maximum Strength Diaper Rash Paste uses 40% zinc oxide to treat and prevent diaper rash discomfort.

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03/08/2024 12:37 pm GMT
Penaten Baby Cream
$9.49 ($1.86 / Ounce)

Penaten Baby Cream contains zinc to help sooth and clear diaper rashes. While it's often been said to be bad for cloth diapers, CDfB recently proved that is it fine on natural fibres in the Great Cloth Diaper Cream Experiment part one.

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03/08/2024 03:46 am GMT

Just make sure to use a fleece liner (you can DIY some fleece liners up without sewing for a few bucks, instructions are here) to protect your diaper from being stained by the zinc cream.

How Do You Stop Ammonia in Cloth Diapers?

Once you have the rash healing with a good cream, it’s time to fix the cause. Here are the steps to stop the ammonia in your cloth diapers:

Step One: Stop Using Soaps and Get a Good Detergent

If you’ve been using a DIY laundry soap, commercial soap, or Charlie’s washing powder, stop immediately and strip your diapers to remove the buildup they have caused. If you haven’t been using these soaps, skip to step two and do NOT strip your diapers as this is only recommended to remove soap scum, it does not remove the ammonia itself.

Instructions on how to strip cloth diapers with RLR are available here. Note: borax, Vinegar, Dawn dish soap, and washing soda are not on the list of stripping products that will work, click the link if you’ve never stripped your diapers before.

You can find help on choosing a good cloth diaper detergent, including plant-based options, free and clear options, and sensitive skin options, here.

Step Two: Stop Using Any Laundry Additives

Stop using bleach and any other laundry additives and correct the ph balance. If you haven’t been using bleach or any other additives, skip to step three.

As usual, the internet is full of really bad advice, and recommending bleaching for ammonia is another example.

If you have been using bleach or any other high PH laundry additives, add a vinegar rinse to your laundry routine for the next few washes. Adding about a 1/2 cup into the rinse of your main wash should be adequate to correct your PH problem and remove the bleach.

Regular old white vinegar is perfectly safe for cloth and your washing machine; you can find more information on using vinegar with cloth diapers here.

Step Three: Create a Measure Method Wash Routine and Do A Swoosh Test

If you have been using a generic wash routine given to you by a Facebook group, or worse Fluff Love University, stop immediately and take the time to create a proper Measure Method Wash Worksheet following the instructions here.

A Measure Method cloth diaper wash routine will take into account your washer size, how many diapers you’re washing, your detergent choice, and your water hardness and tell you exactly how to wash your diapers with the correct amount of detergent.

If you have been using a Measure Method wash routine, it’s time to check your numbers and consider posting to the Cloth Diapers for Beginners Facebook group for help.

No matter what routine you’ve been using, also stop and check for detergent buildup by doing a “swoosh test” (instructions here). This is an important part because if you have detergent buildup you’ll need to rinse your diapers clean and make sure your washing machine is also clear of buildup before continuing with your new Measure Method routine.

It sounds like a lot right now, I know, but just go one step at a time, you’ve got this!

Step Four: Spray Nighttime Diapers with Bac-Out and Use Fleece Liners and Cream

If your kiddo is older and the only problem is nighttime diapers, you can control things with a few stop-gap measures.

Specifically, put a good layer of diaper cream on your baby before bed, and use a fleece liner to help keep the wetness off their skin and protect the diaper from the cream. When your baby wakes up, spray your nighttime diapers with Bac-Out, an enzyme cleaner pretreatment that will neutralize the ammonia before you put it into the washer with the rest of your diaper laundry.

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03/08/2024 11:22 am GMT

If you don’t want to invest in Bac-Out, you can use regular white vinegar in a spray bottle as well, it just doesn’t smell as nice (it will change the ammonia smell to a dirty bar-alley urine smell, if that makes sense).

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Neutralizing the nighttime diaper every time should help keep the PH of your nighttime diapers balanced, and prevent ammonia from being transferred to your other diapers regularly.

If Not Wash Related, Schedule a Pediatrician Visit

If you haven’t been using soap, haven’t been using bleach or other additives, don’t have any barnyard smells or detergent buildup (as seen in the swoosh test mentioned above), and can’t nail down a wash-related cause it may be a health-related issue and it’s a good idea to schedule a pediatrician visit as soon as possible.

While you’re waiting for your appointment, keep up with the cream and cornstarch to calm the rash and keep a record of the rashes, when they happened, and what your baby ate prior to the rash.

Also, rinse or spray out your wet diapers in the same way you do your soiled diapers. Diluting the urine before putting them in the washer can slow ammonia buildup if it’s being caused by a bodily function.

Conclusion: Ammonia Happens, But it’s Fixable

As usual, I’ve thrown a lot at you with this post. Rest assured, while ammonia happens, it’s usually fairly easy to correct once you narrow things down by thinking about what you and your baby have been up to before the rash.

Think about what you’ve been up to, eliminate the causes that don’t fit, and work on the ones that are possibilities. You’ve got this.

And as always, contact your pediatrician for any rash you don’t feel comfortable dealing with on your own, and know that rashes happen whether in cloth diapers or disposables.

April Duffy

April is the founder of Cloth Diapers for Beginners and author of The Cloth Diaper Wash & Care Handbook. Since 2015, April has helped well over 75,000 parents and caregivers cloth diaper their children through this website, her book, her YouTube Channel, and the Cloth Diapers for Beginners Facebook Group.